Fluid operated dipper trip



April 25, 1933. c; MORIN 1,905,183

FLUID OPERATED DIPPER TRIP Filed Feb. 2'6. 1931 s Sheets-Sheet l INVENTOR. 65 0/?66 6. MM?! ATTORNEYS.

April 25, 1933. s. G. MORIN 1,905,183

FLUID OPERATED DIPPER TRIP Filed Feb. 26. 1951 5 Sheets-Sheet 2 IN VEN TOR. 650M: 6. MOR/N A TTORNEYS.

April 25, 1933. MORlN 1,905,183

FLUID OPERATED DIPPER TRIP Filed Feb. 26. 1931 3 SheetsSheet 5 "a; LG. INVENTOR.

62mm: 6. MOE/N A TTORNEYS.

Patented Apr. 25, 1933 UNITED sures.

JGEOBGE e. monnv, or KOLYOKE'MASSAGHUSETI'S FLUID OPERATED DIPPER TRIP Application filed February 26, 1931. Sex-10.110. 518,488; i

This invention relates to dipper trips and has particular reference to. improvements in tripping mechanisms of the type mounted upon the boom of :an excavating machine at substantially the point of intersection-f theboom with the dipper stick. One object of: the invention is to provide :a deviceOi this'character which .is extremely simple and reliable in operation. A further object is 19 to provide a device of this character which is of a self-contained character, all operating parts being contained within the drum upon which the tripping cable is wound.

A further object is toprovide a device of '15 this character which is adaptable equally for excavatingmach-ines inwhich the crowdin mechanism. includes a rotating shaft or for that type of machine in which the crowding mechanism employs a stationary shaft witharotating pinion thereon.

Other objects will appear from the follow ing description and claims. I

Referring to the drawings, t

Fig. '1 is a fragmentary and somewhat diagrammatic side elevation of an excavating machine to which my invention has bee applied;

Fig. 2 is a sectional .detail corresponding to a portion of Fig. 4 but having the parts 0 in a different position of operation;

Fig. 3 is a central section through a dipper tripping device embodying my invention;

Fig. 4 is a view on line of Fig. 3; Fig. 5 is a view similar to a portion of Fig. 1 showing a slightly diiferent arrangement of apparatus; and

Fig. 6 is a View similarrto a portion of Fig.

3 showing the modification of Fig. '5.

40 The device will be described first, with reference to the preferred embodiment shown in Fig. 1 to Fig.4 inclusive. In Fig. 1 the cab frame of a conventional excavating machine has been indicated at 10. A

'45 boom 11 is :pivotedxto this frame at 12 and has a dipper stick 13 movable .upon it in the usual way. The dipper stick has been shown :as slidable in a yokelt mounted upon a cross shaft l5asecured to the boom; :In

' ithe modification of Fig. 1 the cross shaft has been shown as rotatable, ,whilein the modification of'Figs. .5 and6 corresponding shaft 15 has been shown -.as,stati-onary. .1; Mounted at the end of the dipper stick is a dipper 16 having its swinging bottom as latched in any of the usual ways. Thepa-ra ticular form of latched-.bottom .n0t being essential :to my invent-ioml have not illustrated it. A chain 17 runs from the latch mechanism to alever 18 pivoted at 19 on the on dipper stick and adapted to bear against the .stop 20, being held thereby a spring 20, Itis preferable that withthe lever 1.8} gainst the stop the chain 17 .besomewhat loosewfor a reason to be described'below. At itsend as the lever 18 carries a pulley 21 .anoundwhich passes acable 22. ,One end of :thiscable is attached to a stationary p0intx23gon1the boom and the :other end is woundupon .-a drum generically indicatedjat '24..

y The construction of the drumis indicated more fully in Figs. 3 and 4. It is there shown as .formed of side members .25 and 26 held to'gether'by bolts 27.. One 0t the sid members carriesan eye .28 to W-hichthe ,end 75 of the tripping cable 22 may be attached. The drum assembly turns freely upon bushings 30 mountedupon a cylindricalmem; ber 31 held asby a set screw 32 .to the shaft 15 and, therefore, rotatable therewith. This I member together @with'the flanges and the web portion 33 of the drum forms anyennw lar chamber 34. A pairof abutments 3 5 and;36 are formed to fit closely withintliis chamber and are secured by screws37 and e 38 respectively to. the web -.and ;to .-the member '31. Formed in the member 31 is a ifluid 00nducti-ng portl39 joined to" an axial =-passage 40. A stufiingbox 41 connects ithis paSSage no with a pipe line 42 adapted to supply pres- .tion of Fig. .4 it is;.cle,arsthat zt'he ahutments dob 35 and 36 will be forced apart as indicated in Fig. 2 in which they are shown at the other limit of their relative motion. The action of the pressure fluid is to move the abutment 35 ,and consequently the drum relative to the member, which, due to its attachment to the shaft 15, may be either stationary or rotating during this operation. A vent 46 is placed preferably in the web 33 at a distance spaced somewhat from the abutment 35 so that shortly before the position of Fig. 2 is reached the vent will pass the relatively stationary abutment 36 and will permit dischargei-ofi-xthe pressure fluid from the port 39 to the atmosphere.

' The annular chamber 34 is completely circular except where interrupted by the two abutments. It-has, as viewed in Fig. 4, two portions, the smaller one being between the closely spaced abutments and connected with the port 39, and the-larger one extending between the outer sides of the abutments and connected with the vent 46. As the drum is rotated to the right in Fig. 4 the vent 46 will finally pass over the abutment 36 and the supply connection between what was initially the larger'of the two portions of the chamber to the outside air will thereupon be cut off. This causes the air entrapped between the abutments to be compressed in any further rotation of the drum, the structure thus acting as a dash pot (Fig. 2) to prevent the abutments striking forcibly against each other. When the drum is rotated in the other direction any shock is taken up by aspring 47 secured to the abutment 36, this spring also serving to insure that the abutments will always have a slight space between them sufficient to permit entrance of pressure fluid from the port 39.

The operation of the device will now b considered. It will be understood that the dipper stick is driven back and forth as may be desired by the interengagement of rack teeth 48 formed upon it with a pinion 49 on the shaft 15, this shaft being driven as usual by the crowding engine. As the dipper stick moves in or out, the distance between the dipper and the boom varies and, therefore, the length of the cable 22 has to be varied in order to prevent the formation of slack. If the dipper'stick is moved to the right in Fig. 1 the drum will likewise be rotated to the right and cablewill be wound up upon it. If the pulley 21 is used, as is preferred, the effective winding diameter of the drum is made twice the pitch diameter of the pinion 49, as it is necessary to wind up twice as much cable as the amount that the dipper travels. If the dipper stick is moved to the left of Fig. 1 the member 31 will be rotated but it has no direct connection with the drum when moved in this direction. The drum, however, is caused When it is desired to exert a tripping tension on the cable 22 the valve 43 is actuated to admit steam to the space between the abutments 35 and 36, causing the drum to rotate relativeto the member 31 an amount sufficient to wind up enough cable to trip the dipper. latch. As soon as the dipper latch has been tripped the valve is of course released, the vent 46, however, serving to prevent damage if release is not accomplished soon enough. r In the customary operation of excavating machines of this type the dipper is'not only moved in and out by meansof the dipper stick but is also raised and lowered by means of the usual hoisting devices,-causing the dipper stick to turn upon the shaft 15 as a pivot. As this occurs the effective length of the cable 22 between its point of attachment 23 and the drum 24 will vary. It is for this purpose that the chain 17 is left slack, the length of the cable being initially adjusted so that in that position of the dipper stickin which the cable tends to be slackest the lever 18 will be resting against the stop 20. As the dipper-stick is swung from'this position the lever 18 will be rocked, such motion being permitted by the spring 20 and the slackness of the chain 17 precluding any tripping action of the latch. It willbe understood that the swing ing motion referred to has no necessary relation to the reciprocating motion imparted by the pinion 49, these motions being carried on either separately or together, depending on theoperation desired by the operator.

In general it will be preferred. to use steam as a motive power since the crowding engine which turns shaft 15 is generally a steam engine- The vent 46 being formed in the surface of the drum is of assistance where steam is used in providing a drain for any water of condensation which may I collect in the chamber 34. It is not necessary that on every actuation of the dipper the water of condensation be completely vented but this should happen with reasonable frequency. Since the member 31 and the drum both rotate the vent 46 will be constantly passing through its position in which it points vertically downward and hence permits the escape of water of condensation. sufiicient number of cases the vent will be pointing downward at the time when it is connected with the steam pressure chamber, and any accumulation of condensed water will, therefore, be prevented. V

The modification shown in Figs. 5 and 16 It has been foundthat in a is generally similar to that previously described, and the parts have, therefore, been denoted by the same reference numerals except where a change is made. Instead of constantly rotating shaft 15 as in the previously described form, the modification now being considered employs a stationary shaft 15', the rack driving pinion 49 being freely turned on the shaftby a suitable gear train. In this form of construction it is generally impractical to connect the member 31 directly with the pinion, particularly when the assembly is to be made in the field, and I have indicated in Figs. 5 and; 6 an alternative method of driving the member 31 so that it may have a speed proportional to' the reciprocating motion of the dipper stick. For this purpose a drum 50 is secured to the member 31 as by bolts 51, and a flange 52 extends from the drum into a groove 53 in the end of the stationary shaft 15. The drum is made in two transversely split sections to permit assembly in this manner. Wound about the drum 50 and suitably secured to it is a cable 55 having an anchorage 56 on the end of the dipper stick remote from the dipper. This cable serves to turn the member 31 toward the right in Fig. 5 as the dipper stick is moved in that direction by the pinion 49'. When the dipper stick is moved in the opposite direction the cable 22 turns the drum to the left. Motion of the drum in this direction, as will be clearly seen in Fig. 4, will also carry the member 31 with it. The cable 55 and the cable 22 thus serve to keep the member 31 in an annular position proportional to the position of the dipper stick, and the cable 55 also serves to hold the member 31 in position when tripping tension is to be applied by the injection of steam between the abutments 35 and 36.

What I claim is:

1. An excavating machine comprising a boom, a dipper strick rotatably and slidably mounted in the boom, a circular member rotatably mounted in the boom substantially at the intersection of the dipper stick and boom, the dipper stick being provided with means making rolling contact with the member, a dipper mounted at the end of the dipper stick and provided with a latched bottom, a drum having rotative coupling to the member and located concentrically therewith, said drum having an effective cable winding diameter equal to twice the effective diameter of the pinion, a pulley connected to the dipper latch, a cable secured to the boom, passing around the pulley, and wound upon the drum, and operator-controlled mechanism for rotating the drum relative to the pinion to cause the cable to be wound thereon and the dipper latch to be tripped.

2. An excavating machine comprising a.

boom, a dipper stick rotatably and slidabl mounted in the boom and provided with rac teeth, a pinion rotatably mounted on the boom so as to mesh with the rack teeth on the dipper stick, a dipper mounted at the end of the dipper stick and provided with a latched bottom, a drum having rotative coupling to the pinion and locatedconcentrically therewith, said drum having an effective cable winding diameter equal to twice the pitch diameter of the pinion, a pulley connected to the dipper latch, a cable secured to the boom, passing around the pulley, and wound upon the drum, and operator-controlled mechanism for rotating the drum relative to the pinion to cause the cable to be wound thereon and the dipper latch to be tripped.

3. An excavating machine comprising a.

boom, a dipper stick rotatably and slidably mounted in the boom, a drum rotatably mounted in the boom substantially at the a positive one-way connection between the two drums, and operator-controlled mechanism for rotating the second drum relative to the first to cause the cable to be wound thereon and the dipper latch to be tripped.

4. An excavating machine comprising a boom, a dipper stick rotatably and slidably mounted in the boom, a drum rotatably mounted in the boom substantially at the intersection of the dipper stick and boom, a cable attached to the end of the dipper stick remote from the dipper and wound upon the drum, a second drum mounted concentrically with the first and having an efiective cable winding diameter equal to twice that of the first, a pulley movably mounted adjacent the dipper and connected to the dipper latch, a cable secured at one end to the boom, passing around said pulley, and wound upon the second drum, and operator-controlled mechanism for rotating the second drum relative to the first to cause the second cable to be wound upon the second drum and the dipper latch to be tripped.

In testimony whereof I have aflixed my signature.

GEORGE G. MORIN. 

